Chevrolet 70 1969 Series, Shop Manual

Page: 783 / 913

TRANSMISSION AND CLUTCH 7-37
Replace all bearings that are not in first class con­
dition.
NOTE: After cleaning and inspecting bearings
as directed, lubricate bearings generously with
lubricant recommended in LUBRICATION (SEC.
0) of this manual; then w rap each bearing in
clean paper until ready to reinstall in transmis­
sion.
2. Remove all portions of old gaskets from parts, using
a stiff brush or scraper.
INSPECTION
1. Inspect rods and shafts for evidence of fatigue. Check
bearing surfaces for scoring or wear.
2. Inspect all parts for discoloration or warpage due to
heat.
3. Examine all gear teeth and splines for chipped, worn,
broken, or nicked teeth or splines. Small nicks or
burrs may be removed with a fine abrasive stone.
4. Inspect the breather assembly to see that it is open
and not damaged.
5. Check all threaded parts for damaged, stripped or
crossed threads.
6. Check all oil passages for obstructions, using brass
rods and air pressure.
7. Replace all gaskets, oil seals, lock wire, cotter pins,
and snap rings. (If snap rings are not damaged or dis­
torted and are not used for sealing as well as retain­
ing, they may be reused).
8. Examine synchronizer assemblies for scoring, wear, or
other damage. Replace synchronizers if not in first
class condition.
9. Inspect housings and covers for cracks, breaks, or
other damage. Since repairs by welding, brazing, etc.,
are not recommended, replace all damaged parts.
10. Inspect all bushings for wear or other damage.
11. Check keys and keyways for condition.
12. Inspect shift forks for wear, distortion, or other dam ­
age.
13. Check springs for free length, compressed length, dis­
tortion, or collapsed coils.
REPAIR
Key numbers in text refer to Figure 13 unless otherwise
specified.
Mainshaft Rear Bearing Cap
1. If inspection shows necessity, press or drive rear bear­
ing cap oil seal assembly (64) out of rear bearing cap
(63). Discard oil seal.
2. Using a suitable sleeve and ham m er or press, drive or
press new oil seal in bore of bearing cap. Lip of oil
seal goes in toward transmission case.
Clutch Release Bearing and Support
1. If inspection shows clutch release bearing assembly on
support are damaged, press bearing off support. Re­
place damaged parts.
2. Using a press and suitable sleeve, press new bearing
on support.
Clutch Housing Replacement
1. Remove nuts and lock washers from clutch housing to
transmission case studs, then remove clutch housing
from transmission case.
2. In order to obtain correct location of clutch housing
on transmission case, the following procedure must be
followed:
a. Install main drive gear (76) and bearing assembly
(77) in transmission case (74).
b. Install drive gear bearing cap (80) over drive
gear (76) and bearing (77) and secure in place
with bolt and lock washer assemblies.
c. Install clutch housing (I) on transmission case
(74), install lock washers and nuts on studs, and
tighten firmly.
d. Remove drive gear bearing cap (80), drive gear
(76), and bearing assembly (77) from transmission
case.
ASSEMBLY OF SUBASSEMBLIES
Key numbers in text refer to Figure 1 I P unless other­
wise specified.
T h e im p o rta n c e of cleanliness can n o t be o v erem ­
phasized. Rebuild of the transmission should not be at­
tempted in a dirty working area. All parts except those
being actually worked on should be kept covered with
clean paper. Avoid nicking, marring, or burring all surfa­
ces. Whenever a common tool is specified, such as a
“ soft” ham m er or a vise with “soft-jaws,” that tool
should be used. Substitution of a hard ham m er for ex­
ample, may seriously damage the transmission. Special
tools mentioned in text and shown in illustrations should
be employed. List of tools will be found in “ S P E C IA L
T O O L S ” at end of this manual.
When assembling the transmission, use new lock wire,
snap rings, cotter pins, gaskets, and oil seals. Lubricate
each moving part with lubricant specified in L U B R IC A ­
T IO N (SEC. 0) of this manual. Coat all bushings with a
light coat of petrolatum before installation.
MAIN DRIVE GEAR ASSEMBLY
1. Lubricate main drive gear bearing (77) and drive gear
shaft (76) with lubricant recommended in LL>BRICA-
T IO N (SEC. 0) of this manual.
2. Start bearing assembly (77) straight on shaft of drive
gear (76) with bearing snap ring toward pilot end of
gear. Support front inner race of bearing and press
gear into bearing tight against front face of gear.
CHEVROLET SERIES 70-80 H EAVY DUTY TRUCK SH O P M A N U A L